Use of 4-tert-butyl-1-cyclohexanol as an antioxidant

ABSTRACT

The use of 4-tert-butyl-1-cyclohexanol as an antioxidant in soaps, shampoos and other cosmetic products, as well as in all-purpose cleaners, is described.

This is a continuation-in-part of application Ser. No. 08/875,887 filedAug. 6, 1997 now U.S. Pat. No. 5,858,958.

TECHNICAL FIELD AND PRIOR ART

The present invention relates to perfumery and cosmetics. It concerns,more particularly, the use of 4-tert-butyl-1-cyclohexanol asantioxidant.

4-Tert-butyl-1-cyclohexanol is a known perfuming ingredient but which isnot used very currently in perfumery as a result of its not too elegantcamphoraceous note. It develops in fact an odor of the woody-patchouli,camphoraceous type. It is also known that this compound is very stableeven in very aggressive media characteristic of soaps, detergents orbleaching products. However, to our knowledge, it has never beensuggested to use this compound as a stabilising agent against oxidationin cleaning or cosmetic products.

DESCRIPTION OF THE INVENTION

We have now discovered that 4-tert-butyl-1-cyclohexanol turns out to bevery efficient as an antioxidant, namely when used in detergent andcosmetic media containing fat materials which are easily oxidised uponexposure to air and/or light and the oxidation products of which developunpleasant odors, particularly of the rancid type.

It is known, for example, that certain types of soaps develop rancid,piquant and fruity odors after only a few weeks of storage in air.Examples for this type of soaps include synthetic and semi-syntheticsoaps as well as non-synthetic soaps consisting of fatty acid salts, insolid or liquid form. Now, we have observed that occurrence of suchmalodors could be entirely prevented, or at least prevented for farlonger storage periods, if 4-tert-butyl-1-cyclohexanol was added tothese soaps.

Similar effects were observed in shampoos or yet in bath or shower gels.

In a general manner, this compound reveals itself as an efficientstabilising agent against oxidation in all the cosmetic and skin or haircleansing products comprising materials which are susceptible of beingoxidised by air and/or light exposure and, as a result, of developingunpleasant odors. In this context, one can cite, in addition to theconsumer products mentioned above, cosmetic creams and milks.

It has also been established that this compound can be useful as ananti-oxidant in other cleaning or detergent products, particularlygeneral use detergents or all-purpose cleaners for hard surfaces,dishwashing products and other, whenever they comprise fat materialssusceptible of being oxidised upon exposure to air or light.

To achieve the effects desired according to the invention,4-tert-butyl-1-cyclohexanol can be added to the soap, shampoo or othertype base either on its own or in admixture with other ingredients ofcurrent use in perfumery, namely usual perfuming co-ingredients,solvents or adjuvants. A more detailed description of the latter is heresuperfluous. Their nature will depend namely of the perfuming effect onewants to achieve, as well as on the type of product to be perfumed, andthe skilled person is able to choose such ingredients on the basis ofher general knowledge in the art and taking inspiration from referencetextbooks such as the book of S. Arctander, Perfume and FlavorChemicals, Montclair, N.J. (1969) or more recent versions thereof,amongst others.

As is apparent from the examples presented further on,4-tert-butyl-1-cyclohexanol reveals itself as a more efficientantioxidant than other agents currently used for this purpose, such asBHT (2,6-di-tert-butyl-p-cresol; origin: Bayer), editronic acid (forexample Turpinal® SL; origin: Henkel, Germany), α- or γ-tocopherol,ascorbic, citric or tartric acids and their salts or esters, thethiodipropionic esters sold under the name of Irganox® (origin: Ciba SC,Basle, Switzerland), like Irganox® PS 800(β,β'-dilaurylthiodipropionate), Irganox® PS 801(β,β'-dimyristylthiodipropionate), Irganox® PS 802(β,β'-distearylthiodipropionate), or Irganox® 1010 [pentaerythritoltetrakis 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], or yet anymixtures of two or more of these products. It goes without saying that4-tert-butyl-1-cyclohexanol can also be used in admixture with theseantioxydants. We observed that excellent results could be obtained when4-tert-butyl-1-cyclohexanol was used in combination with BHT, editronicacid, the tocopherols (α- or γ), the Irganox® type antioxidants, citricacid, ascorbic acid or tartric acid or yet their esters. The bestresults, however, were obtained when 4-tert-butyl-1cyclohexanol was usedin combination with at least one antioxidant of the Irganox® type (PS800, PS 801, PS 802 or 1010), or with at least one of the tocopherols(α- or γ-), or in combination with at least one antioxidant of bothtypes.

As has been cited above, 4-tert-butyl-1-cyclohexanol can be used asantioxidant in perfuming or cosmetic compositions, in compositions forcleaning skin or hair, or yet in all-purpose cleaning compositions, andthe invention also concerns such compositions.

The nature of the base compositions to which this compound is added isquite immaterial here, all the soap, cosmetic or detergent type basescurrently used in the corresponding industries or known in the art beingconvenient for preparing compositions according to the invention wherein4-tert-butyl-1-cyclohexanol is incorporated as antioxidant. The examplesof such base compositions presented hereafter are cited for illustrativepurposes only and it is clear that other current bases of similar type,containing materials susceptible of being oxidised, can be used insteadof those here given as examples.

The concentrations in which the above-mentioned compound can be added tothe various products to impart its anti-oxidation effect vary in a widerange of values. Beneficial effects can already be observed atconcentrations of the order of 0.005 to 0.01% by weight, relative to theweight of the finished product, i.e. soap, shampoo, shower gel or other.However, it is preferred according to the invention to use this compoundin concentrations of, or above, 0.05% by weight, relative to the weightof the finished product. More preferably, such products will contain inthe order of 0.05 to 0.5% by weight of 4-tert-butyl-1-cyclohexanol. Whenthe cyclohexanol of the invention is used in combination with theantioxidants of the Irganox® type or with the tocopherols (α- or γ-),these further antioxidants will be used in concentrations of the orderof 0.01 to 0.2% by weight, preferably of the order of 0.05 to 0.1% byweight, relative to the total weight of the finished product. Soaps,shampoos or yet shower or bath gels are embodiments of compositionsaccording to the invention, and the same applies to the nourishing orbeauty creams or milks, or other.

Moreover, it is to be noted that it is a known fact that, in certainmedia where hydrolysis occurs readily, the addition thereto of4-tert-butyl-1-cyclohexyl acetate can be equivalent to adding4-tert-butyl-1-cyclohexanol, said acetate being susceptible of beingpartially or totally hydrolysed to form this corresponding alcohol. Itgoes therefore without saying that the invention also relates to anycompositions or products of the type above-mentioned which contain, orto which there is added, said 4-tert-butyl-1-cyclohexyl acetate, and thepH of which is susceptible of causing the formation therefrom of thecorresponding 4-tert-butyl-1-cyclohexanol, in an amount sufficient forthe latter to impart its antioxidant effect to the composition orproduct.

When used in perfuming compositions, which can themselves be added tothe above-mentioned products to impart thereto certain fragrances,4-tert-butyl-1-cyclohexanol can make up 5 to 50% of the weight of theperfuming composition.

The invention will now be described in more detail by way of thefollowing examples, wherein the temperatures are indicated in degreesCelsius.

EMBODIMENTS OF THE INVENTION EXAMPLE 1

Stabilisation of a semi-synthetic type soap

A soap was prepared by admixture of the following ingredients, accordingto current methods.

    ______________________________________                                        Ingredients          % by weight                                              ______________________________________                                        Sodium cocoylisethionate.sup.1)                                                                    51.0                                                       Sodium dodecylbenzenesulfonate.sup.2) 2.0                                     Sodium isethionate.sup.3) 5.0                                                 Stearic acid 25.0                                                             Sodium salt of C.sub.12 to C.sub.18 fatty acids 17.0                          Total 100.0                                                                 ______________________________________                                         .sup.1) origin: PPG Industries, USA                                           .sup.2) origin: Chem. Werke Huls, Germany                                     .sup.3) origin: Witco Chem. Comp., USA                                   

To this base composition there were added the ingredients cited in thetable hereafter, in the amounts indicated, to prepare samples ofstabilised soap bases.

                  TABLE I                                                         ______________________________________                                                    Sample                                                              % by weight, relative to the base                                           Ingredients   A       B      C      D    E                                    ______________________________________                                        Tenox ® .sup.1) GT II                                                                   --      0.07   --     0.05 --                                     Irganox ® .sup.2) PS-800 0.05 -- 0.05 0.05 --                             Citric acid* 0.20 0.20 0.20 0.20 0.20                                         BHT 0.07 -- 0.07 -- --                                                        Turpinal ® .sup.3) SL -- -- 0.10 -- --                                    4-tert-butyl-1-cyclohexanol -- -- -- 0.10 0.20                              ______________________________________                                         *50% in water                                                                 .sup.1) tocopherol; origin: Eastman Chemicals                                 .sup.2) dilaurylthiodipropionate; origin: CibaGeigy AG                        .sup.3) etidronic acid; origin: Henkel                                   

Soaps were stamped with these stabilised bases in the conventionalmanner.

Soaps A to E thus obtained were stored in glass containers, at 40° andthen subjected to evaluation by a panel of expert perfumers, on a blindtest.

The panel judged that soaps A to C developed a fatty, butter and rancidodor, which could not be found in soap D, nor in soap E, both of which,furthermore, presented a slightly floral fragrance.

EXAMPLE 2

Stabilisation of solid soaps

A stabilising mixture was prepared by means of 1 g of4-tert-butyl-1-cyclohexanol, 0.5 g of Tenox® GT II and 0.5 g of Irganox®PS-800.

By means of the base composition described in example 1, perfumed soapbases were then prepared, by adding the ingredients indicated hereafter,in the amounts cited:

                  TABLE II                                                        ______________________________________                                                    Sample                                                              % by weight, based on the weight of the base                                  composition                                                                 Ingredients   A       B      C      D    E                                    ______________________________________                                        Hedionc ® .sup.1)                                                                       0.05    0.05   0.05   0.05 0.05                                   Rosewood essential oil 0.10 -- -- -- --                                       Bergamot essential oil -- 0.10 -- -- --                                       Benzoin essential oil* -- -- 0.10 -- --                                       Cedar essential oil -- -- -- 0.10 --                                          Geranium essential oil -- -- -- -- 0.10                                     ______________________________________                                         *at 20% in dipropyleneglycol                                                  .sup.1) methyl dihydrojasmonate; origin: Firmenich SA, Geneva, Switzerlan

Soaps A to E were stamped with these soap bases. At the same time, soapsA to E' were obtained from the bases A to E, but to which there had beenfurther added 0.3% of the stabilising mixture cited above.

These ten soaps were stored at 40° during one month and then evaluatedon a blind test and two by two, that is, A and A', B and B' C and C', Dand D', and E and E', by a panel of experts.

The result of these evaluations showed that soaps A' to E' had a goododor, without any fatty, rancid note, whereas soaps A to E developedfragrances in which the unpleasant rancid notes were clearly detected.

EXAMPLE 3

Stabilisation of solid soaps

A standard soap base was prepared in a conventional manner by admixingthe following ingredients:

    ______________________________________                                        Ingredients           % by weight                                             ______________________________________                                        Sodium salts of beef tallow fatty acids                                                             60.0                                                      Sodium salts of coconut oil fatty acids 26.0                                  Water 14.0                                                                    Total 100.0                                                                 ______________________________________                                    

To this soap base there was then added 1.5 to 2% by weight of one of theperfuming compositions A or B containing the following ingredients, toprepare perfumed soap bases:

    ______________________________________                                                        Composition A                                                                          Composition B                                        Ingredients       (Parts by weight)                                           ______________________________________                                        Phenethylol       3500       3500                                               Citronellol 2000  2000                                                        Iralia ® .sup.1) 300 300                                                  Geraniol 600 600                                                              Diphenyl ether 200 200                                                        Benzyl acetate 800 800                                                        Phenylethyl acetate 400 400                                                   3-Methyl-5-phenyl-1-pentanol.sup.2) 400 400                                   Dorinia SA.sup.3) 100 100                                                     Vert de lilas.sup.4) 200 200                                                  50%* 15-Pentadec-(11,12)-enolide.sup.5)  50  50                               4-tert-Butyl-1-cyclohexanol --  1000                                          Total 9000  10000                                                           ______________________________________                                         *in dipropyleneglycol                                                         .sup.1) methylionone; origin: Firmenich SA, Geneva, Switzerland               .sup.2) origin: Firmenich SA, Geneva, Switzerland                             .sup.3) origin: Firmenich SA, Geneva, Switzerland                             .sup.4) (2,2dimethoxyethyl)benzene; origin: GivaudanRoure, Vernier,           Switzerland                                                                   .sup.5) origin: Firmenich SA, Geneva, Switzerland                        

Soaps A and B were conventionally stamped with the soap bases perfumedby means of the compositions A, respectively B.

After storage for a month at 40°, the two soaps were evaluated by apanel of expert perfumers, on a blind test. In the opinion of thelatter, soap B developed a floral, rose, green, musky type odor, whereassoap A presented clearly detectable fatty, rancid notes, which renderedits odor distinctly less pleasant than that of soap B.

EXAMPLE 4

Preparation of a liquid shampoo

A liquid shampoo, intended for body and hair cleaning, was prepared byadmixing the following ingredients, according to the usual techniques:

    ______________________________________                                        Ingredients      % by weight                                                  ______________________________________                                        Texapon ® .sup.1) N28                                                                      25.0                                                           Medialan ® .sup.2) LD 7.0                                                 Demineralised water 64.4                                                      NaCl 1.5                                                                      Citric acid 0.5                                                               Kathon ® .sup.3) CG 0.1                                                   Comperland ® .sup.4) KD 1.5                                               Total 100.0                                                                 ______________________________________                                         .sup.1) sodium ethersulfate; origin: Henkel                                   .sup.2) lauryl sarcosinate; origin: Hoechst                                   .sup.3) preserver; origin: Rohm & Haas                                        .sup.4) coconut acid diethanolamide; origin: Henkel                      

To this unfragranced base shampoo there were added 0.1% by weight of4-p-tert-butyl-1-cyclohexanol, 0.05% by weight of Tenox® GH, 0.05% byweight of Irganox® PS-800 and 0.1% by weight of citric acid, to obtain astabilised shampoo. Separate plastic containers were filled with thisstabilised shampoo and with the base shampoo.

After storing for one month at 40°, the two shampoos were evaluated by apanel of experts, on a blind test. The latter indicated a markedpreference for the stabilised shampoo, which presented no traces offatty odor notes, whereas the base shampoo had a well marked acrid andfat odor.

EXAMPLE 5

Stability test

In order to test the antioxidant effect of 4-tert-butyl-1-cyclohexanolin perfuming compositions susceptible of air oxidation, there was addedto a mixture of orange terpenes (containing 95% by weight of limonene),0.1% by weight of the above-mentioned cyclohexanol, 0.05% by weight ofIrganox® PS-800 and 0.05% by weight of Tenox® GT II.

The mixture of terpenes on their own, and the mixture of terpenes withthe above-mentioned stabilising compounds, were subjected to a Rancimattype test (see for example, M. W. Laubli, Lebensmittelchemie 48, page134). In order to do this, the two mixtures wee heated to 110°, underair, while measuring their conductivity. It was thus observed that theconductivity of the unstabilised mixture of terpenes indicated itsoxidation after 2 h of heating, whereas the terpene mixture whichcontained the stabilising agents only started to show oxidation after5.5 h of heating in air.

EXAMPLE 6

Stabilisation of an all-purpose cleaner

An all-purpose cleaner was prepared by admixing the followingingredients, according to the usual art methods.

    ______________________________________                                        Ingredients       % by weight                                                 ______________________________________                                        Water             74.7                                                          Sodium carbonate 3.0                                                          Sodium citrate 2.0                                                            Sodium cumolsulfonate.sup.1) 7.0                                              Marlon ® .sup.2) A 375 10.0                                               Tergitol ® .sup.3) 15-S-9 3.0                                             Perfume.sup.4) 0.3                                                            Total 100.0                                                                 ______________________________________                                         .sup.1) origin: Huls AG, Germany                                              .sup.2) sodium dodecylbenzene sulfonate; origin: Huls AG, Germany             .sup.3) C.sub.11 -C.sub.15 ethoxylated secondary alcohol; origin: Union       Carbide, USA                                                                  .sup.4) BLue Water, n.sup.o 114 338; origin: Firmenich SA, Geneva,            Switzerland                                                              

To this perfumed base composition, there was then added 0.1% by weightof sweet almond oil to obtain an all-purpose cleaner base. With thelatter there was then prepared a novel cleaning composition according tothe invention via addition of 0.2% by weight of4-tert-butyl-1-cyclohexanol. The all-purpose cleaner base and the novelall-purpose cleaner were then stored, in plastic bottles, underultraviolet light during 8 h. At the end of this storage period, bothbottles were evaluated, on a blind test, by a panel of experts, whoindicated that the product containing 4-tert-butyl-1-cyclohexanolpresented no traces of any fatty notes, whereas the base detergent had arancid almond oil odor.

I claim:
 1. A method of stabilizing a composition which contains anoxidizable fat material subject to oxidation by air and/or light, themethod comprising: including 4-tert-butyl-1-cyclohexanol in thecomposition in an amount effective to act as an antioxidant against airor light.
 2. The method of claim 1, which further comprises adding tothe composition at least one compound selected from the group consistingof 2,6-di-tert-butyl-p-cresol, α-tocopherol, γ-tocopherol, ascorbicacid, citric acid, tartaric acid and esters thereof,β,β'-dilaurylthiodipropionate, β,β'-dimyristylthiodipropionate,β,β'-distearylthiodipropionate and pentaerythritol tetrakis3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, in an amount effectiveto act as a further antioxidant for the composition.
 3. The method ofclaim 1, which further comprises adding to the composition at least onecompound selected from the group consisting of α-tocopherol andγ-tocopherol or from the group consisting ofβ,β'-dilaurylthiodipropionate, β,β'-dimyristylthiodipropionate,β,β'-distearylthiodipropionate and pentaerythritol tetrakis3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or at least onecompound from each group.
 4. The method of claim 1, wherein thecomposition is a perfuming composition.
 5. The method of claim 4,wherein the amount of 4-tert-butyl-1-cyclohexanol is 5 to 50% by weightof the composition.
 6. The method of claim 1, wherein the composition isa cosmetic composition, an all-purpose cleaning composition, a soap, abath or shower gel, or a shampoo.
 7. The method of claim 1, wherein thecomposition is a liquid or solid soap.
 8. The method of claim 2, whereinthe composition is a liquid or solid soap.
 9. The method of claim 3,wherein the composition is a liquid or solid soap.
 10. The method ofclaim 9, wherein the amount of 4-tert-butyl-1-cyclohexanol is 0.05 to0.5% by weight of the composition and the amount of each of theantioxidants furthermore added is 0.05 to 0.1% by weight of thecomposition.
 11. A composition comprising a cosmetic, cleansing orperfuming ingredient that is subject to oxidation by air, light, or bothair and light, and 4-tert-butyl-1-cyclohexanol in an amount effective toact as an antioxidant.
 12. The composition of claim 11, furthercomprising adding to the composition at least one compound selected fromthe group consisting of 2,6-di-tert-butyl-p-cresol, α-tocopherol,γ-tocopherol, ascorbic acid, citric acid, tartaric acid and estersthereof, β,β'-dilaurylthiodipropionate, β,β'-dimyristylthiodipropionate,β,β'-distearylthiodipropionate and pentaerythritol tetrakis3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, in an amount effectiveto act as a further antioxidant for the composition.
 13. The compositionof claim 11, further comprising adding to the composition at least onecompound selected from the group consisting of α-tocopherol andγ-tocopherol, or from the group consisting ofβ,β'-dilaurylthiodipropionate, β,β'-dimyristylthiodipropionate,β,β'-distearylthiodipropionate and pentaerythritol tetrakis3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or at least onecompound from each group.
 14. The composition of claim 11, wherein thecomposition is a perfuming composition.
 15. The composition of claim 14,wherein the amount of 4-tert-butyl-1-cyclohexanol is 5 to 50% by weightof the composition.
 16. The composition of claim 11, wherein thecomposition is a cosmetic composition, an all-purpose cleaningcomposition, a soap, a bath or shower gel, or a shampoo.
 17. Thecomposition of claim 11, wherein the composition is a liquid or solidsoap.
 18. The composition of claim 12, wherein the composition is aliquid or solid soap.
 19. The composition of claim 13, wherein thecomposition is a liquid or solid soap.
 20. The composition of claim 19,wherein the amount of 4-tert-butyl-1-cyclohexanol is 0.05 to 0.5% byweight of the composition and the amount of each of the furtherantioxidants added is 0.05 to 0.1% by weight of the composition.